Tractor unit with on-board regenerative braking energy storage for stopover hvac operation without engine idle

ABSTRACT

A through the road (TTR) hybridization strategy is proposed to facilitate introduction of hybrid electric vehicle technology in a significant portion of current and expected trucking fleets. In some cases, the technologies can be retrofitted onto an existing vehicle (e.g., a trailer, a tractor-trailer configuration, etc.). In some cases, the technologies can be built into new vehicles. In some cases, one vehicle may be built or retrofitted to operate in tandem with another and provide the hybridization benefits contemplated herein. By supplementing motive forces delivered through a primary drivetrain and fuel-fed engine with supplemental torque delivered at one or more electrically-powered drive axles, improvements in overall fuel efficiency and performance may be delivered, typically without significant redesign of existing components and systems that have been proven in the trucking industry.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is divisional of U.S. patent application Ser. No.15/898,396, filed Feb. 16, 2018, which claims priority to U.S.Provisional Patent Application No. 62/460,734 filed Feb. 17, 2017, theentire disclosures of which are incorporated by reference herein.

The present application is related to U.S. Provisional Application No.62/403,000, filed Sep. 30, 2016, entitled “VEHICLE THERMAL MANAGEMENTSYSTEM AND RELATED METHODS,” naming Thomas Joseph Healy and Eric Weberas inventors. The present application is also related to the followingapplications each filed May 2, 2016, each entitled “MOTOR VEHICLEACCESSORY TO INCREASE POWER SUPPLY AND REDUCE FUEL REQUIREMENTS”, andeach naming Thomas Joseph Healy as inventor: (1) U.S. application Ser.No. 15/144,769; (2) U.S. application Ser. No. 15/144,775; and (3)International Application No. PCT/US2016/030482. Each of theaforementioned applications is incorporated by reference herein.

BACKGROUND Field of the Invention

The invention relates generally to hybrid vehicle technology, and inparticular to a system and method to intelligently control regenerationand reuse of captured energy.

Description of the Related Art

Every year the U.S. trucking industry consumes 51 billion gallons offuel, accounting for over 30% of overall industry operating costs. Inaddition, the trucking industry spends over $100 billion on fuelannually, and the average fuel economy of a tractor-trailer (e.g., an18-wheeler) is about 6.5 miles per gallon. For trucking fleets facedwith such large fuel costs, any way to offset those costs would be worthconsidering. Hybrid technology has been in development for use in thetrucking industry for some time, and some hybrid trucks have entered themarket. However, existing systems are generally focused on hybridizingthe tractor, while any attached trailer remains a passive load. Thus,the extent to which the fuel efficiency of a tractor-trailer may beimproved is limited to the extent to which the fuel efficiency of thehybrid tractor is improved. Therefore, improved techniques andfunctional capabilities are desired.

SUMMARY

In some embodiments of the present invention, a vehicle includes: avehicle frame; a fuel-fed engine and plural drive axles attached to thevehicle frame, wherein at least one of the drive axles is coupled via adrivetrain to the fuel-fed engine to drive at least a pair of wheels; atleast one other of the drive axles being an electrically-powered driveaxle configured to supply supplemental torque to one or more additionalwheels of the vehicle and to thereby supplement, while the vehicletravels over a roadway and in at least some modes of operation, primarymotive forces applied through the drivetrain; an energy store on thevehicle, the energy store configured to supply the electrically powereddrive axle with electrical power and further configured to receiveenergy recovered using the drive axle in a regenerative braking mode ofoperation; and a heating, ventilation or cooling (HVC) system on thevehicle, the heating, ventilation or cooling system coupled to receiveelectrical power from the energy store, wherein for stopover operationand without idling of the fuel-fed engine, the energy store powers theHVC system

In some embodiments, the vehicle is a tractor unit for use in atractor-trailer vehicle configuration, and the HVC system is anauxiliary system, substantially separate from a main heating ventilatingor cooling system of the vehicle, configured to regulate temperaturewithin at least a portion of a cabin of the tractor unit during stopoverand without idling of the fuel-fed engine.

In some embodiments, the tractor unit is a 6×2 tractor unit retrofittedto replace an otherwise dead axle of a tandem pair with theelectrically-powered drive axle.

In some embodiments, the retrofitted electrically-powered drive axle iscoupled to a brake line of the tractor unit for control of theregenerative braking mode of operation.

In some embodiments, the energy store includes: a battery; a batterymanagement system for controllably maintaining a desired state of charge(SoC) of the energy store during the over-the-roadway travel; and a heatexchanger for at least moderating temperature of the battery during theover-the-roadway travel.

In some embodiments, the heat exchanger includes a fluid-air heatexchanger exposed to airflow during over-the-roadway travel and coupledinto a compressor-based loop for subambient cooling of the battery atleast during the over-the-roadway travel, the compressor-based loopfurther coupled to supply subambient cooling to the cabin of the tractorunit, at least selectively during the stopover operation, via afluid-air heat exchanger of the HVC system.

In some embodiments, the energy store further includes at least oneadditional electrical storage device having discharge rate and/orcapacity characteristics that differ from the battery; and the batterymanagement system controllably maintains the desired SoC includingstates of charge of the battery and of the at least one additionalelectrical storage device.

In some embodiments, the at least one additional electrical storagedevice includes either or both of an ultracapacitor and additionalbattery-type storage.

In some embodiments, the vehicle further includes an in-cabin controlinterface coupled to the battery management system, the controlinterface including: an in-cabin display of state of charge for theenergy store; and mode control for selectively controlling an operatingmode of the battery management system, wherein in at least oneselectable mode, energy recovered using the electrically-powered driveaxle in the regenerative braking mode is used to bring the energy storeto a substantially full state of charge, and wherein in at least anotherselectable mode, state of charge is managed to a dynamically varyinglevel based on actual or predicted requirements for supplemental motiveforces during over-the-roadway travel.

In some embodiments, the vehicle further includes: an inverter coupledbetween the energy store and an in-cabin electrical power interface tosupply auxiliary AC power in the cabin of the vehicle during stopoveroperation and without idling of the fuel-fed engine.

In some embodiments of the present invention, a tractor for use in atractor-trailer vehicle configuration includes: at least oneelectrically-powered drive axle coupled to a frame of the tractor andconfigured to supply supplemental torque to one or more wheels of thetractor, while the vehicle travels over a roadway and in at least somemodes of operation; a battery on the tractor, the battery configured tosupply the electrically-powered drive axle with electrical power andfurther configured to receive energy recovered using theelectrically-powered drive axle in a regenerative braking mode ofoperation; and a heating, ventilation or cooling (HVC) system on thevehicle, the heating, ventilation or cooling system coupled to receiveelectrical power from the battery.

In some embodiments, the tractor further includes: at least one fuel-fedengine powered drive axle coupled to the frame of the tractor, whereinthe at least one fuel-fed engine powered drive axle is coupled via adrive shaft to a fuel-fed engine to drive at least a pair of wheels andto thereby provide primary motive forces.

In some embodiments, the HVC system is an auxiliary system,substantially separate from a main heating ventilating or cooling systemof the tractor, configured to regulate temperature within at least aportion of a cabin of the tractor unit during stopover and withoutidling of the fuel-fed engine.

In some embodiments, the tractor is a 6×2 tractor unit retrofitted toreplace an otherwise dead axle of a tandem pair with theelectrically-powered drive axle.

In some embodiments, the retrofitted electrically-powered drive axle iscoupled to a brake line of the tractor unit for control of theregenerative braking mode of operation.

In some embodiments, the tractor further includes: a battery managementsystem for controllably maintaining a desired state of charge (SoC) ofthe battery array during the over-the-roadway travel; and a heatexchanger for at least moderating temperature of the battery during theover-the-roadway travel.

In some embodiments, the tractor further includes an in-cabin controlinterface coupled to the battery management system, the controlinterface including: an in-cabin display of state of charge for thebattery array; and mode control for selectively controlling an operatingmode of the battery management system, wherein in at least oneselectable mode, energy recovered using the electrically-powered driveaxle in the regenerative braking mode is used to bring the battery arrayto a substantially full state of charge, and wherein in at least anotherselectable mode, state of charge is managed to a dynamically varyinglevel based on actual or predicted requirements for supplemental motiveforces during over-the-roadway travel.

In some embodiments of the present invention, a method includes:supplying supplemental torque to one or more wheels of a vehicle for usein a tractor-trailer vehicle configuration using an electrically powereddrive axle on the vehicle to supplement, while the vehicle travels overa roadway and in at least some modes of operation, primary motive forcesapplied through a separate drivetrain of the vehicle; supplying theelectrically powered drive axle with electrical power from an energystore on the vehicle, the energy store configured to receive and storeenergy recovered using the electrically powered drive axle in aregenerative braking mode of operation; and supplying electrical powerfrom the energy store to a heating, ventilation or cooling (HVC) systemon the vehicle.

In some embodiments, the vehicle is a 6×2 tractor unit retrofitted toreplace an otherwise dead axle of a tandem pair with theelectrically-powered drive axle.

In some embodiments, the energy store includes: a battery; a batterymanagement system for controllably maintaining a desired state of charge(SoC) of the energy store during the over-the-roadway travel; and a heatexchanger for at least moderating temperature of the battery during theover-the-roadway travel.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and notlimitation with reference to the accompanying figures, in which likereferences generally indicate similar elements or features.

FIG. 1A depicts a bottom view of a hybrid suspension system, inaccordance with some embodiments;

FIG. 1B depicts a top view of the hybrid suspension system, inaccordance with some embodiments;

FIG. 1C depicts an exemplary tractor-trailer vehicle, including thehybrid suspension system and an adapted hybrid system, in accordancewith some embodiments;

FIG. 1D depicts a bottom view of the adapted hybrid system, inaccordance with some embodiments;

FIG. 1E depicts a bottom view of an alternative embodiment of theadapted hybrid system, in accordance with some embodiments;

FIGS. 2A-2F illustrate a control system circuit, which may be housedwithin the hybrid suspension system of FIGS. 1A and 1B, or within theadapted hybrid system of FIGS. 1D and 1E, in accordance with someembodiments;

FIG. 3 depicts an exemplary controller area network (CAN bus) that maybe used for communication of the various components of the controlsystem circuit of FIGS. 2A-2F, in accordance with some embodiments;

FIG. 4 is a functional block diagram of a hardware and/or softwarecontrol system, in accordance with some embodiments;

FIG. 5A is a flow diagram providing a method for controlling a hybridsuspension system and/or an adapted hybrid system, in accordance withsome embodiments;

FIG. 5B is a flow diagram providing an aspect of the method of FIG. 5Afor controlling the hybrid suspension system and/or the adapted hybridsystem, in accordance with some embodiments;

FIG. 6A is an exemplary functional block diagram for controlling thehybrid suspension system, in accordance with some embodiments;

FIG. 6B is an exemplary functional block diagram for controlling theadapted hybrid system, in accordance with some embodiments;

FIG. 6C is an exemplary functional block diagram for controlling boththe hybrid suspension system and the adapted hybrid system, inaccordance with some embodiments; and

FIG. 7 illustrates an embodiment of an exemplary computer systemsuitable for implementing various aspects of the control system andmethods of FIGS. 5A and 5B, in accordance with some embodiments.

Skilled artisans will appreciate that elements or features in thefigures are illustrated for simplicity and clarity and have notnecessarily been drawn to scale. For example, the dimensions orprominence of some of the illustrated elements or features may beexaggerated relative to other elements or features in an effort to helpto improve understanding of embodiments of the present invention.

DESCRIPTION

The following disclosure provides many different embodiments, orexamples, for implementing different features of the provided subjectmatter. Specific examples of components and arrangements are describedbelow to simplify the present disclosure. These are, of course, merelyexamples and are not intended to be limiting. In addition, the presentdisclosure may repeat reference numerals and/or letters in the variousexamples. This repetition is for the purpose of simplicity and clarityand does not in itself dictate a relationship between the variousembodiments and/or configurations discussed.

The present disclosure provides systems and methods for providing anenergy management system and related methods. In particular, embodimentsof the present disclosure provide a hybridized suspension assembly thatmay be coupled underneath a trailer, for example, as a replacement to apassive suspension assembly. In various examples, the trailer may betowed by a powered vehicle, such as a fuel-consuming tractor. Asdescribed in more detail below, the hybridized suspension assemblyoperates independently of the powered vehicle and is configured tooperate in at least one of a power assist mode, a regeneration mode, anda passive mode. By effectively collecting and processing a variety ofsensor data, telematics data, and/or other relevant data, embodiments ofthe present disclosure further provide intelligent control methods tosimultaneously optimize fuel consumption of the powered vehicle, as wellas energy consumption of the hybrid suspension assembly. Among otheradvantages, embodiments disclosed herein provide for a significantreduction in fuel consumption (e.g., an average of about 30%), abuilt-in auxiliary power unit (APU), enhanced stability control,improved trailer dynamics, and a host of other benefits, at least someof which are described in more detail below.

Hybrid Suspension System

Referring now to FIGS. 1A and 1B, illustrated therein is a hybridsuspension system 100. As described in more detail below, the hybridsuspension system 100 may include a frame 110, a suspension, one or moredrive axles (e.g., such as a drive axle 120), at least one electricmotor-generator (e.g., such as an electric-motor generator 130) coupledto the at least one or more drive axles, an energy storage system (e.g.,such as a battery array 140), and a controller (e.g., such as a controlsystem 150). In accordance with at least some embodiments, the hybridsuspension system 100 is configured for attachment beneath a trailer. Asused herein, the term “trailer” is used to refer to an unpowered vehicletowed by a powered vehicle. In some cases, the trailer may include asemi-trailer coupled to and towed by a truck or tractor (e.g., a poweredtowing vehicle). By way of example, FIG. 1C illustrates atractor-trailer vehicle 160 that includes a tractor 165 coupled to andoperable to tow a trailer 170. In particular, and in accordance withembodiments of the present disclosure, the hybrid suspension system 100is coupled underneath the trailer 170, as a replacement to a passivesuspension assembly, as discussed in more detail below. For purposes ofthis discussion, the tractor 165 may be referred to generally as a“powered towing vehicle” or simply as a “powered vehicle”.

To be sure, embodiments of the present disclosure may equally be appliedto other types of trailers (e.g., utility trailer, boat trailer, traveltrailer, livestock trailer, bicycle trailer, motorcycle trailer, agooseneck trailer, flat trailer, tank trailer, farm trailer, or othertype of unpowered trailer) towed by other types of powered towingvehicles (e.g., pickup trucks, automobiles, motorcycles, bicycles,buses, or other type of powered vehicle), without departing from thescope of this disclosure. In various embodiments, the powered towingvehicles may further include vehicles utilizing a variety oftechnologies and fuel types such as diesel, gasoline, propane,biodiesel, ethanol (E85), compressed natural gas (CNG), hydrogeninternal combustion engine (ICE), homogeneous charge compressionignition (HCCI) engine, hydrogen fuel cell, hybrid electric, plug-inhybrid, battery electric, and/or other type of fuel/technology.Regardless of the type of technology and/or fuel type, the poweredtowing vehicle may have a particular fuel efficiency. As describedbelow, and among other advantages, embodiments of the present disclosureprovide for improved fuel efficiency of the powered towing vehicle, asdescribed in more detail herein. More generally, and in accordance withvarious embodiments, the hybrid suspension system 100 described hereinis configured for use with any type of trailer or powered towingvehicle. In addition, the hybrid suspension system 100 is configured tooperate autonomously from the powered towing vehicle. As used herein,“autonomous” operation of the hybrid suspension system 100 is used todescribe an ability of the hybrid suspension system 100 to operatewithout commands or signals from the powered towing vehicle, toindependently gain information about itself and the environment, and tomake decisions and/or perform various functions based on one or morealgorithms stored in the controller, as described in more detail below.

A trailer, as typically an unpowered vehicle, includes one or morepassive axles. By way of example, embodiments of the present disclosureprovide for replacement of the one or more passive trailer axles withone or more powered axles. For example, in at least some embodiments,the hybrid suspension system 100 may replace a passive tandem axle witha powered tandem axle, as shown in the example of FIG. 1C. In accordancewith the present disclosure, the hybrid suspension system 100 isconfigured to provide, in a first mode of operation, a motive rotationalforce (e.g., by an electric motor-generator coupled to a drive axle) topropel the hybrid suspension system 100, and thus the trailer underwhich is attached, thereby providing an assistive motive force to thepowered towing vehicle. Thus, in some examples, the first mode ofoperation may be referred to as a “power assist mode”. Additionally, insome embodiments, the hybrid suspension system 100 is configured toprovide, in a second mode of operation, a regenerative braking force(e.g., by the electric motor-generator coupled to the drive axle) thatcharges an energy storage system (e.g., the battery array). Thus, insome examples, the second mode of operation may be referred to as a“regeneration mode”. In some examples, the hybrid suspension system 100is further configured to provide, in a third mode of operation, neithermotive rotational nor regenerative braking force such that the trailerand the attached hybrid suspension system 100 are solely propelled bythe powered towing vehicle to which the trailer is coupled. Thus, insome examples, the third mode of operation may be referred to as a“passive mode”.

In providing powered axle(s) to the trailer (e.g., by the hybridsuspension system 100), embodiments of the present disclosure result ina significant reduction in both fuel consumption and any associatedvehicle emissions, and thus a concurrent improvement in fuel efficiency,of the powered towing vehicle. In addition, various embodiments mayprovide for improved vehicle acceleration, vehicle stability, and energyrecapture (e.g., via regenerative braking) that may be used for avariety of different purposes. For example, embodiments disclosed hereinmay use the recaptured energy to apply the motive rotational force usingthe electric motor-generator and/or provide on-trailer power that may beused for powering a lift gate, a refrigeration unit, a heatingventilation and air conditioning (HVAC) system, pumps, lighting,communications systems, and/or providing an auxiliary power unit (APU),among others. It is noted that the above advantages and applications aremerely exemplary, and additional advantages and applications will becomeapparent to those skilled in the art upon review of this disclosure.

Referring again to FIG. 1A, illustrated therein is a bottom view of thehybrid suspension system 100 which shows the frame 110, the drive axle120, a passive axle 125, and wheels/tires 135 coupled to ends of each ofthe drive axle 120 and the passive axle 125. In addition, the electricmotor-generator 130 is coupled to the drive axle 120 by way of adifferential 115, thereby allowing the electric motor generator 130 toprovide the motive rotational force in the first mode of operation, andto charge the energy storage system (e.g., the battery array) byregenerative braking in the second mode of operation. While shown ashaving one drive axle and one passive axle, in some embodiments, thehybrid suspension system 100 may have any number of axles, two or moredrive axles, as well as multiple electric-motor generators on each driveaxle. In addition, axles of the hybrid suspension system (e.g., thedrive axle 120 and the passive axle 125) may be coupled to the frame 110by a leaf spring suspension, an air suspension, a fixed suspension, asliding suspension, or other appropriate suspension. In someembodiments, the wheels/tires 135 coupled to ends of one or both of thedrive axle 120 and the passive axle 125 may be further coupled to asteering system (e.g., such as a manual or power steering system),thereby providing for steering of the hybrid suspension system 100 in adesired direction.

With reference to FIG. 1B, illustrated therein is a top view of thehybrid suspension system 100 showing the battery array 140 and thecontrol system 150. In various embodiments, the battery array 140 andthe control system 150 may be coupled to each other by an electricalcoupling 145. In addition, the electric motor-generator 130 may becoupled to the control system 150 and to the battery array 140, therebyproviding for energy transfer between the battery array 140 and theelectric motor-generator 130. In various examples, the battery array 140may include one or more of an energy dense battery and a power densebattery. For example, in some embodiments, the battery array 140 mayinclude one or more of a nickel metal hydride (NiMH) battery, a lithiumion (Li-ion) battery, a lithium titanium oxide (LTO) battery, a nickelmanganese cobalt (NMC) battery, a supercapacitor, a lead-acid battery,or other type of energy dense and/or power dense battery.

In some embodiments, one or more aspects of the hybrid suspension system100 may be adapted for use as part of the tractor 165. With reference toFIG. 1C, and in some embodiments, such an adapted hybrid system 101 mayinclude various aspects of the hybrid suspension system 100, asdescribed above, which are coupled to and/or integrated with existingcomponents of the tractor 165 to provide the adapted hybrid system 101.In some examples, the adapted hybrid system 101 may provide forreplacement of the one or more passive axles of the tractor 165 with oneor more powered axles. Thus, in various embodiments, the adapted hybridsystem 101 may be used to provide a motive rotational force (e.g., in afirst mode, or power assist mode, of operation) to the powered towingvehicle (e.g., to the tractor 165). Additionally, in some embodiments,the adapted hybrid system 101 is configured to provide a regenerativebraking force (e.g., in a second mode, or regeneration mode, ofoperation) that charges an energy storage system (e.g., the batteryarray). In some examples, the adapted hybrid system 101 is furtherconfigured to provide neither motive rotational nor regenerative brakingforce (e.g., in a third mode, or passive mode, of operation).

It is noted that the adapted hybrid system 101 may be used separatelyand independently from the hybrid suspension system 100 attached to thetrailer. Thus, for example, advantages of the various embodimentsdisclosed herein (e.g., reduced fuel consumption and emissions, improvedfuel efficiency, vehicle acceleration, vehicle stability, and energyrecapture) may be realized by the adapted hybrid system 101 apart fromthe hybrid suspension system 100. This may be advantageous, forinstance, when the tractor 165 is driven without the attached trailer.To be sure, when the tractor 165 is used to tow a trailer and in someembodiments, the hybrid suspension system 100 and the adapted hybridsystem 101 may be cooperatively operated to provide a greater motiverotational force to, or recapture a greater amount of energy from, thetractor-trailer vehicle 160 than either of the hybrid suspension system100 or the adapted hybrid system 101 may be able to provide or recaptureon their own. In at least some embodiments, the adapted hybrid system101 may be independently used (e.g., apart from the hybrid suspensionsystem 100) to recapture energy that can subsequently be used to providepower to tractor 165 systems and/or to trailer systems. For example,such power may be used to power a lift gate, a refrigeration unit, aheating ventilation and air conditioning (HVAC) system, pumps, lighting,communications systems, and/or to provide an auxiliary power unit (APU),among others.

With reference to FIG. 10, illustrated therein is a bottom view of theadapted hybrid system 101 coupled to and/or integrated with the tractor165. As shown, the tractor 165 may include a cab 172, a frame 174, asteering axle 176, an engine-powered axle 178, an electric axle 180, andwheels/tires 135 coupled to ends of each of the steering axle 176, theengine-powered axle 178, and the electric axle 180. A steering wheel maybe coupled to the steering axle 176 to turn and/or otherwise control adirection of travel of the tractor 165. In various embodiments, thetractor 165 further includes an engine 182, a torque converter 184coupled to the engine 182, a transmission 186 coupled to the torqueconverter 184, a drive shaft 188 coupled to the transmission 186, and adifferential 190 coupled to the drive shaft 188. The differential 190may be further coupled to the engine-powered axle 178, thereby providingtorque to the wheels coupled to ends of the engine-powered axle 178. Aspart of the adapted hybrid system 101, and in various embodiments, theelectric motor-generator 130 may be coupled to the electric axle 180 byway of the differential 115, thereby allowing the electricmotor-generator 130 to provide the motive rotational force in the firstmode of operation, and to charge the energy storage system (e.g., thebattery array) by regenerative braking in the second mode of operation.In some embodiments, the electric axle 180 may include multipleelectric-motor generators coupled thereto. As shown in FIG. 10, theadapted hybrid system 101 may also include the battery array 140 and thecontrol system 150, for example, coupled to each other by an electricalcoupling, thereby providing for energy transfer between the batteryarray 140 and the electric motor-generator 130. The battery array 140may include any of a variety of battery types, as described above.

Referring to FIG. 1E, illustrated therein is a bottom view of analternative embodiment of the adapted hybrid system 101 coupled toand/or integrated with the tractor 165. In particular, in the example ofFIG. 10, the engine-powered axle 178 is disposed between the steeringaxle 176 and the electric axle 180, which is disposed at a back end(e.g., opposite the cab 172) of the tractor 165. Alternatively, in theexample of FIG. 1E, the electric axle 180 is disposed between thesteering axle 176 and the engine-powered axle 178, which is disposed ata back end (e.g., opposite the cab 172) of the tractor 165. While notshown in FIG. 1E for clarity of illustration, the adapted hybrid system101 provided therein may also include the battery array 140 and thecontrol system 150, as described above. It is also noted that FIG. 10and FIG. 1E illustrate a 6×2 tractor unit, where the electric axle 180replaces what would have been an otherwise dead axle of the tandem pairof rear axles.

Control System Architecture and Components

As discussed above, the hybrid suspension system 100 and/or the adaptedhybrid system 101 are configured to operate autonomously and in at leastthree modes of operation: (i) a power assist mode, (ii) a regenerationmode, and (iii) a passive mode. In particular, and in variousembodiments, the hybrid suspension system 100 and/or the adapted hybridsystem 101 are operated in one of these three modes by way of thecontrol system 150 (e.g., in conjunction with suitable program code, asdiscussed below). Various aspects of the control system 150, includingsystem architecture and exemplary components, are described in moredetail below with reference to FIGS. 2A-2F, 3, and 4.

Referring first to FIGS. 2A-2F, illustrated therein is a control systemcircuit 200 that may be housed within the control system 150. It isnoted that the control system circuit 200, and the components shown anddescribed herein are merely exemplary, and other components and/orcircuit architecture may be used without departing from the scope ofthis disclosure. FIG. 2A shows an AC motor controller 202, which may beused to actuate the electric motor-generator 130. By way of example, andin some cases, the AC motor controller 202 may include a Gen4 Size 8controller manufactured by Sevcon USA, Inc. of Southborough, Mass. Insome embodiments, the AC motor controller 202 is coupled to an AC motorcontroller relay 238 (FIG. 2D). As described below with reference toFIG. 3, the AC motor controller 202 may communicate with othercomponents of the control system circuit 200 by way of a controller areanetwork (CAN bus). FIG. 2B shows an electric motor-generator 204, whichmay be the electric motor-generator 130 discussed above, and which maybe actuated by the AC motor controller 202. In some examples, theelectric-motor generator 204 may include an electric motor-generatormanufactured by Remy International, Inc. of Pendleton, Ind. FIG. 2Cillustrates a water pump 206 coupled to a water pump relay 218, a waterfan 208 coupled to a wafer fan relay 220, an oil pump 210 coupled to anoil pump relay 222, an oil fan 212 coupled to an oil fan relay 224, anda ground bus bar 214. Each of the water pump 206, the water fan 208, theoil pump 210, and the oil fan 212 may be coupled to a voltage supply 216(and thus enabled) by way of their respective relay, where the relaysare coupled to and actuated by a master control unit 228 (FIG. 2D). Inaddition, the ground bus bar 214 may be coupled to a ground plane 226(FIG. 2D), and each of the water pump 206, the water fan 208, the oilpump 210, and the oil fan 212 may be coupled to the ground plane 226 byway of the ground bus bar 214.

In addition to the master control unit 228, FIG. 2D illustrates a DC-DCpower supply 230 coupled to a DC-DC control relay 236, a brake pressuresensor 232 coupled to the master control unit 228, a ground faultdetector (GFD) 234 coupled to a battery management system (BMS)/GFDrelay 240, and the AC motor controller relay 238. The DC-DC power supply230 may be coupled to the voltage supply 216 (and thus enabled) by wayof the DC-DC control relay 236, which is coupled to and actuated by amaster control unit 228. Similarly, the GFD 234 and a “Key On-” input ofa BMS 242 (FIG. 2E) may be coupled to the voltage supply 216 by way ofthe BMS/GFD relay 240, which is also coupled to and actuated by themaster control unit 228. The AC motor controller 202 may also be coupledto the voltage supply 216 (and thus enabled) by way of the AC motorcontroller relay 238, which is also coupled to and actuated by themaster control unit 228. In various embodiments, the DC-DC power supply230 and the master control unit 228 may communicate with othercomponents of the control system circuit 200 by way of the CAN bus, asdiscussed below. FIG. 2E shows the “Key On-” input of a BMS 242 coupledto the BMS/GFD relay 240, as discussed above. In addition, a “Key On+”input of the BMS 242 may be coupled directly to the voltage supply 216,as shown in FIG. 2F. In some embodiments, the BMS 242 may alsocommunicate with other components of the control system circuit 200 byway of the CAN bus, as discussed below.

Referring specifically to FIG. 2F, illustrated therein is a compressor244 coupled to a cooling relay 248, an attitude and heading referencesystem (AHRS) 246 coupled to an AHRS relay 252, and an optional inverterrelay 250. By way of example, the compressor may include a variablefrequency drive (VFD) or variable speed drive (VSD) compressor. Thecompressor 244 may be coupled to the voltage supply 216 (and thusenabled) by way of the cooling relay 248, which is coupled to andactuated by a master control unit 228. Similarly, the AHRS 246 may becoupled to the voltage supply 216 (and thus enabled) by way of the AHRSrelay 252, which is coupled to and actuated by a master control unit228. In some embodiments, the AHRS 246 may communicate with othercomponents of the control system circuit 200 by way of the CAN bus, asdiscussed below. In various embodiments, the control system circuit 200further includes an inverter, as shown below in FIG. 4, that may becoupled to the DC-DC power supply 230 and which may be optionallyenabled/disabled using the inverter relay 250 by the master control unit228. Moreover, in various embodiments, the inverter is coupled to theelectric motor-generator 204 to provide power to, or receive power from,the electric motor-generator 204. It is again noted that the descriptionof the control system circuit 200 is merely exemplary, and otheraspects, advantages, and useful components will be evident to thoseskilled in the art, without departing from the scope of this disclosure.For example, in various embodiments, the control system circuit 200 mayalso include one or more of a fuse and relay module, a 12 volt battery,a fuse block, one or more battery disconnect switches, one or moreelectrical contactors, a pre-charge resistor, and/or other components asknown in the art.

With reference now to FIG. 3, illustrated therein is a controller areanetwork (CAN bus) 300 used for communication of the various componentsof the control system circuit 200 with one another. Generally, a CAN busis a vehicle bus standard designed to allow microcontrollers and otherdevices such as electronic control units (ECUs), sensors, actuators, andother electronic components, to communicate with each other inapplications without a host computer. In various embodiments, CAN buscommunications operate according to a message-based protocol.Additionally, CAN bus communications provide a multi-master serial busstandard for connecting the various electronic components (e.g., ECUs,sensors, actuators, etc.), where each of the electronic components maybe referred to as a ‘node’. In various cases, a CAN bus node may rangein complexity, for example from a simple input/output (I/O) device,sensors, actuators, up to an embedded computer with a CAN bus interface.In addition, in some embodiments, a CAN bus node may be a gateway, forexample, that allows a computer to communicate over a USB or Ethernetport to the various electronic components on the CAN network. In variousembodiments, CAN bus nodes are connected to each other through a twowire bus (e.g., such as a 1200 nominal twisted pair) and may beterminated at each end by 120Ω resistors.

In particular, the CAN bus 300 is illustrated as a linear bus terminatedat each end by 120Ω resistors. In some embodiments, the CAN bus 300includes an ISO 11898-2 high speed CAN bus (e.g., up to 1 Mb/s). By wayof example, the CAN bus 300 is shown as including as nodes, for example,the AC motor controller 202, the BMS 242, the AHRS 246 (sensor), themaster control unit 228, the DC-DC power supply 230 (actuator), andtelematics unit 302 (smart sensor). In some embodiments, the telematicsunit 302 may include a global positioning system (GPS), an automaticvehicle location (AVL) system, a mobile resource management (MRM)system, a wireless communications system, a radio frequencyidentification (RFID) system, a cellular communications system, and/orother telematics systems. In some embodiments, the telematics unit 302may also include the AHRS 246. In accordance with various embodiments,at least some of the sensors, actuators, and other electronic componentswhich are not included (e.g., shown in FIG. 3) as CAN bus nodes, maythemselves be coupled to the CAN bus 300 by way of one or more of theCAN bus nodes. For example, a voltage meter (sensor), a current meter(sensor), and one or more electrical contactors (actuators) may becoupled to the CAN bus 300 by way of the BMS 242. Similarly, the waterpump 206 (actuator), the water fan 208 (actuator), the oil pump 210(actuator), the oil fan 212 (actuator), the GFD 234 (sensor), aninverter, the brake pressure sensor 232, a trailer weight sensor, aswell as other actuators, sensors, and/or electronic components may becoupled to the CAN bus 300 by way of the master control unit 228. Insome examples, the electric motor-generator 204 (actuator) is coupled tothe CAN bus 300 by way of the AC motor controller 202.

Referring now to FIG. 4, illustrated therein is control system diagram400 which provides further detail regarding connections and/orcommunication between and among the various control system components,some of which have been shown and described above (e.g., as part of thecontrol system circuit 200 and/or the CAN bus 300). By way of example,the control system diagram 400 shows that the master control unit 228 isconfigured to operate as a ‘Master’ controller, while each of the BMS242 and the AC motor controller 202 are configured to operate as ‘Slave’controllers and are thereby under control of the master control unit228. In some embodiments, and as illustrated in the control systemdiagram 400, the master control unit 228 provides for control (e.g.,actuation of and/or receipt of a sensor output) for each of the waterpump 206, the water fan 208, the oil pump 210, the oil fan 212, atrailer weight sensor 408, the DC-DC power supply 230, an inverter 412,the AHRS 246, a telematics unit 410, the GFD 234, and the brake pressuresensor 232. Additionally, the BMS 242 provides for control (e.g.,actuation of and/or receipt of a sensor output) for each of a voltagemeter 402, a current meter 404, and one or more electrical contactors406. In some embodiments, the AC motor controller 202 provides forcontrol (e.g., actuation) of the electric motor-generator 204, asdiscussed above.

Control Methods, Generally

Various aspects of the hybrid suspension system 100 and the adaptedhybrid system 101 have been described above, including aspects of thecontrol system architecture and related components. It particular, ithas been noted that the hybrid suspension system 100 and the adaptedhybrid system 101 are operated, by way of the control system 150 andsuitable program code, in at least three modes of operation: (i) a powerassist mode, (ii) a regeneration mode, and (iii) a passive mode. In atleast some embodiments, the program code used to operate the controlsystem 150 may reside on a memory storage device within the mastercontrol unit 228 (FIG. 2D). In addition, the master control unit 228 mayinclude a microprocessor and/or microcontroller operable to execute oneor more sequences of instructions contained in the memory storagedevice, for example, to perform the various methods described herein. Insome cases, one or more of the memory storage, microprocessor, and/ormicrocontroller may reside elsewhere within the hybrid suspension system100, within the adapted hybrid system 101, or even at a remote locationthat is in communication with the hybrid suspension system 100 or theadapted hybrid system 101. In some embodiments, a general purposecomputer system (e.g., as described below with reference to FIG. 7) maybe used to implement one or more aspects of the methods describedherein.

With reference now to FIG. 5A, illustrated therein is a method 500 ofcontrolling a hybrid suspension system, such as the hybrid suspensionsystem 100 and/or the adapted hybrid system 101 described above withreference to FIG. 1. Generally, and in some embodiments, the method 500provides a method for determining how much torque should be provided bythe hybrid suspension system 100 and/or the adapted hybrid system 101,and as such in which mode to operate the hybrid suspension system 100and/or the adapted hybrid system 101 (e.g., power assist, regeneration,or passive), in order to keep the hybrid suspension system 100, atrailer to which the hybrid suspension system 100 is coupled, and apowered vehicle towing the trailer, moving along their currenttrajectory at a substantially constant speed. Among other advantages,embodiments of the method 500 provide for a reduction in both fuelconsumption and any associated vehicle emissions, and thus a concurrentimprovement in fuel efficiency, of a powered vehicle towing the trailer,as well as improved vehicle acceleration, vehicle stability, and energyrecapture (e.g., via regenerative braking).

It is also noted that while performing the method 500, aspects of thepresent disclosure may additionally receive data from, send data to,actuate, other otherwise interact with various components of the controlsystem circuit 200 and the CAN bus 300, described above. Thus, one ormore aspects discussed above may also apply to the method 500. Moreover,additional process steps may be implemented before, during, and afterthe method 500, and some process steps described above may be replacedor eliminated in accordance with various embodiments of the method 500.

Referring now to the method 500, the method 500 begins at block 502where trailer data is received from one or more on-board sensors. Asused herein, the term “on-board sensors” may be used to describe sensorsthat are coupled to or part of the hybrid suspension system 100, sensorsthat are coupled to or part of a trailer to which the hybrid suspensionsystem 100 is attached, as well as remote sensors that may communicate(e.g., by way of cellular, wireless, RF, satellite, or other suchcommunication) data to a receiver or transceiver that is coupled to orpart of the hybrid suspension system 100 or the trailer. In someembodiments, the described sensors may be coupled to or part of theadapted hybrid system 101 and/or may be coupled to or part of thetractor 165 to which the adapted hybrid system 101 is attached. Invarious embodiments, the sensors may include one or more of a brakepressure sensor (e.g., such as the brake pressure sensor 232), analtitude and heading reference system (e.g., such as the AHRS 246), oneor more smart sensors (e.g., such as the telematics unit 302) which mayinclude a global positioning system as well as other smart sensorsand/or telematics systems as described above, a trailer weight sensorwhich may include an air bag pressure sensor or other type of weightsensor, a speed sensor, a gyroscope, an accelerometer, a magnetometer, alateral acceleration sensor, a torque sensor, an inclinometer, and/orother suitable sensor. In various embodiments, the sensed trailer datais sent to the master control unit 228 for further processing. Forexample, in some embodiments, the received trailer data (e.g., thesensor output) may be filtered to smooth the sensor data and therebymitigate anomalous sensor values. In some cases, such filtering andsmoothing may be accomplished using moving averages and Kalman filters,although other smoothing and/or filtering techniques may also be used.In at least some examples, an estimated braking torque is obtained fromthe brake pressure sensor, an estimated weight of the trailer isobtained from the air bag pressure sensor, and a trailer accelerationand roadway incline are both obtained from the AHRS.

The method 500 then proceeds to block 504 where based at least in parton the trailer data, a total estimated torque is computed. In someembodiments, the total estimated torque includes an estimated torque tomaintain movement of the hybrid suspension system 100, and a trailer towhich the hybrid suspension system 100 is coupled, along their currenttrajectory at a substantially constant speed. In embodiments when thetrailer is at least partially towed by a powered vehicle, the totalestimated torque further includes an estimated torque to maintainmovement of the hybrid suspension system 100, the coupled trailer, andthe powered vehicle, along their current trajectory at a substantiallyconstant speed. For purposes of this discussion, the hybrid suspensionsystem 100, the coupled trailer, and the powered vehicle may becollectively referred to as “a hybrid trailer vehicle system (HTVS)”.Thus, in some embodiments, the tractor-trailer vehicle 160 of FIG. 1Cmay be referred to as an HVTS. In some embodiments, for example when thetractor 165 is driven without the attached trailer, the total estimatedtorque may include an estimated torque to maintain movement of thetractor 165 (e.g., the powered vehicle) along its current trajectory ata substantially constant speed. In some embodiments, when the trailer isat least partially towed by a powered vehicle, one or more computationsmay be performed with respect to each of the hybrid suspension system100 and the adapted hybrid system 101 so as to cooperatively determinean estimated torque to be applied at each of the hybrid suspensionsystem 100 and the adapted hybrid system 101 to maintain movement of theHTVS along its current trajectory at a substantially constant speed.

In an embodiment of block 504, computing the total estimated torque mayinclude computing one or more of a plurality of forces acting on theHTVS. For example, computing the total estimated torque may includecomputing a driver input torque (e.g., throttle/braking of the poweredvehicle), an air drag torque, a road drag torque, a road grade torque,and an acceleration torque, among others. In some embodiments, the airdrag torque and the road drag torque may be dependent on a speed atwhich the HTVS is traveling. In some cases, the road grade torque may bedependent on an incline/decline of a roadway on which the HTVS istraveling. By way of example, the driver of the powered vehicle of theHTVS may actuate an air brake system. In such cases, embodiments of thepresent disclosure may utilize an air brake pressure to calculate abraking torque component of the total estimated torque. In someembodiments, the driver input torque may be substantially equal to a sumof the air drag torque, the road drag torque, the road grade torque, andthe acceleration torque. In various embodiments, the total estimatedtorque computed at block 504 may include a currently-applied (e.g.,instantaneous) HTVS torque. Based in part on the total estimated torqueand an estimate and/or prediction of a driver-applied torque, asdiscussed in more detail below, a specified torque may be applied by wayof the hybrid suspension system 100 to one or more trailer axles.Moreover, in some embodiments and based in part on the total estimatedtorque and an estimate and/or prediction of a driver-applied torque, aspecified torque may be applied by way of one or both of the hybridsuspension system 100 and the adapted hybrid system 101.

The method 500 then proceeds to block 506 where a torque applied by apowered vehicle towing the trailer is computationally estimated (e.g.,by the control system 150). Stated another way, in embodiments of block506, a torque applied by a driver of the powered vehicle (e.g., byapplying throttle or braking) is estimated, for example, as a result ofthe hybrid suspension system 100 being autonomous from the poweredvehicle and thus not having direct feedback regarding driver inputs(e.g., throttle/braking). In some embodiments, a driver-applied torquemay also be estimated, for example, by the adapted hybrid system 101. Insome embodiments, the driver-applied torque may also be predicted. Thus,in some examples, a currently-applied torque may be estimated and asubsequently applied torque may be predicted. In some embodiments, theestimated and/or predicted driver-applied torque may be based on aplurality of factors such as past driver behavior, current driverbehavior, road conditions, traffic conditions, weather conditions,and/or a roadway grade (e.g., road incline or decline). As used herein,the term “driver behavior” may be used to describe a driver's operationof the powered vehicle, for example, including application of throttle,braking, steering, as well as other driver-controlled actions.Additionally, and in various embodiments, at least some of the factorsused to estimate and/or predict the driver-applied torque may includedata received from one or more of the on-board sensors, described above,including GPS or inclinometer data that may be used to determine apresent roadway grade and/or predict an upcoming roadway grade. Forexample, if the upcoming roadway grade includes a positive grade (e.g.,an incline), the driver may in some embodiments be expected to applyadditional throttle. In some cases, if the upcoming roadway gradeincludes a negative grade (e.g., a decline), the driver may in someembodiments be expected to apply the brakes (e.g., of the poweredvehicle). In some embodiments, if the upcoming roadway grade issubstantially flat, the driver may in some embodiments be expected toneither apply additional throttle nor apply the brakes. In someexamples, at least some of the factors used to estimate and/or predictthe applied torque may further include traffic data, weather data, roaddata, or other similar data. Similarly, if the upcoming roadway includesheavy traffic, poor road conditions (e.g., pot holes, unpaved sections,etc.), or if weather has caused hazardous driving conditions (e.g.,rain, flooding, strong crosswinds, etc.), the driver may in someembodiments be expected to apply the brakes. Thus, in accordance withsome embodiments, knowledge of an upcoming roadway grade, combined witha plurality of other data (e.g., traffic, weather, road data) and thedriver's current and/or past behavior may be used to estimate and/orpredict the driver-applied torque. It will be understood that the driverbehaviors discussed above, with respect to roadway grade androad/weather conditions, are merely exemplary. Various other behaviors(e.g., apply throttle during a negative grade or apply brakes during apositive grade) are possible as well, without departing from the scopeof the present disclosure.

The method 500 then proceeds to block 508 where based at least in parton the estimated and/or predicted torque (block 506) and the totalestimated torque (block 504), a specified trailer torque is computed andapplied to one or more of the trailer axles. In some cases, a torque toapply to the electric axle of the tractor 165 is computed and applied.In particular, the specified trailer torque is applied to the one ormore of the trailer axles by way of the hybrid suspension system 100, asdescribed herein. In some cases, based at least in part on the estimatedand/or predicted torque (block 506) and the total estimated torque(block 504), a specified torque may be computed and applied to theelectric axle of the tractor 165 by way of the adapted hybrid system101. Additionally, in an embodiment of block 508, the hybrid suspensionsystem 100 and/or the adapted hybrid system 101 are operated in theappropriate one of the at least three modes of operation (e.g., powerassist, regeneration, or passive) in order to provide the specifiedtrailer torque and/or torque to the electric axle of the tractor 165. Insome embodiments, the specified trailer torque, or torque to apply tothe electric axle of the tractor 165 is computed, at least in part, byplugging in the estimated and/or predicted driver-applied torque into anenergy optimization algorithm that utilizes an equivalent consumptionminimization strategy (ECMS) to simultaneously optimize the fuelconsumption of the powered vehicle and the energy usage (e.g., batterycharge) of the hybrid suspension system 100 and/or the adapted hybridsystem 101.

An aspect of the energy optimization algorithm is illustrated in moredetail in FIG. 5B, which provides a method 550. In some embodiments, themethod 550 may be performed as part of, or in addition to, the method500. For example, in some cases, the method 550 may be performed as partof block 508 of the method 500, where the specified torque is computedand applied to the one or more trailer axles, and/or to the electricaxle of the tractor 165. By way of example, the method 550 begins atblock 552 where a first plurality of torques that may be applied by thepowered vehicle, and a second plurality of torques that may be appliedat the trailer, and/or at the electric axle of the tractor 165 (e.g.,applied by the electric motor-generator), are determined. In someembodiments, the first plurality of torques may include a range oftorque values which the powered towing vehicle is capable of providing(e.g., by way of a fuel-consuming engine, an electric motor, or othermeans of providing a motive force). Similarly, and in some embodiments,the second plurality of torques may include a range of torque valueswhich the hybrid suspension system 100 and/or the adapted hybrid system101 is capable of providing (e.g., by way of the energy storage systemand the electric motor-generator coupled to one or more drive axles orelectric axles).

The method 550 then proceeds to block 554, where the first plurality oftorques is mapped onto a fuel usage map. For example, in someembodiments, a difference between the total estimated torque (block 504)and the second plurality of torques (e.g., each torque of a range ofpossible torque values which the hybrid suspension system 100 and/or theadapted hybrid system 101 can provide) is determined, where thedifference provides a set of corresponding torque values that would beprovided by the powered vehicle (e.g., by the engine of the poweredvehicle). In various embodiments, the set of corresponding torque valuesmay be used to generate a torque-to-fuel usage map for the poweredvehicle. At block 556 of the method 550, the second plurality of torquesmay be used to similarly generate a torque-to-energy usage map for thehybrid suspension system 100 and/or the adapted hybrid system 101.

Thereafter, at block 558 of the method 550, an optimal combination of afirst torque from the first plurality of torques, and a second torquefrom the second plurality of torques, is selected. By way of example,and in an embodiment of block 558, the torque-to-energy usage map may beconverted to another torque-to-fuel usage map, so that mappings of thepowered vehicle and the hybrid suspension system 100 and/or the adaptedhybrid system 101 may be more readily compared. In some cases, thetorque-to-fuel usage map corresponding to the hybrid suspension system100 and/or the adapted hybrid system 101 is subtracted from thetorque-to-fuel usage map corresponding to the powered vehicle (e.g., theengine of the powered vehicle), thereby resulting in a combined poweredvehicle/hybrid suspension system usage map. Thereafter, in someembodiments, an optimal (e.g., minimum) fuel usage from the combinedusage map is determined, including a corresponding index value. In somecases, the corresponding index value is then used to select an optimaltorque value for the hybrid suspension system 100 and/or the adaptedhybrid system 101 from the torque-to-energy usage map, and the optimaltorque value for the hybrid suspension system 100 and/or the adaptedhybrid system 101 is applied, in an embodiment of both blocks 508 and558. In a more general sense, embodiments of the present disclosure maybe used to estimate a current torque demand of the HTVS. Using theestimated torque demand, at least some embodiments may be used todetermine an amount of fuel efficiency gain (e.g., of the poweredvehicle) and/or energy efficiency gain (e.g., of the hybrid suspensionsystem 100 and/or the adapted hybrid system 101) that may be achieved byoperating the hybrid suspension system 100 and/or the adapted hybridsystem 101 in a particular mode, while applying a particular torque,thereby providing for selection of the optimal torque value for thehybrid suspension system 100 and/or the adapted hybrid system 101.

With reference now to FIG. 6A, illustrated therein is an exemplaryfunctional block diagram 600 for controlling the hybrid suspensionsystem 100, described above. In particular, the block diagram 600illustrates exemplary relationship, in at least some embodiments, amongvarious components of an HVTS, such as the tractor-trailer vehicle 160of FIG. 1C. Moreover, at least some aspects of the methods 500, 550,discussed above, may be better understood with reference to FIG. 6A. Forexample, FIG. 6A illustrates the autonomous nature of the hybridsuspension system 100, where the hybrid suspension system 100 is able tooperate without direct commands or signals from the powered towingvehicle (e.g., such as the tractor 165), to independently gaininformation about itself, the trailer 170, and the environment (e.g., byway of the trailer sensing system), and to make decisions and/or performvarious functions based on one or more algorithms stored in the controlsystem 150.

The autonomous nature of the hybrid suspension system 100 is furtherexemplified, in at least some embodiments, by the functional blockdiagram 600 including two separate control loops, a hybrid suspensionsystem control loop 610 and a powered towing vehicle control loop 620.In the powered vehicle control loop 620, a driver 622 may apply athrottle 624 or a brake 626, which is then applied to the poweredvehicle (e.g., such as the tractor 165). In various embodiments, aresponse of the powered vehicle to the applied throttle 624/brake 626(e.g., acceleration/deceleration of the powered vehicle) may be providedas feedback to the driver 622, which the driver 622 may then furtherrespond to by applying additional throttle 624 or brake 626, or neitherthrottle 624/brake 626. In some examples, the powered vehicle may alsoprovide feedback (e.g., to the driver 622) via throttle 624/brake 626inputs.

Independent from the powered vehicle control loop 620, the hybridsuspension control loop 610 may operate in a substantially similarmanner to the methods 500, 550 described above. For example, in at leastsome embodiments, the hybrid suspension control system 150 may receivetrailer data from a trailer sensor system 602, which may include any ofthe one or more sensors discussed above. In some cases, the trailersensor system 602 may include the on-board sensors discussed above. Insome embodiments, the control system 150 may compute a total estimatedtorque and computationally estimate a torque applied by the poweredvehicle 165 (e.g., which may include estimating throttle and/orbraking). In some embodiments, based on the total estimated torque andthe computationally estimated torque of the powered vehicle, a specifiedtrailer torque may be computed and applied to the one or more traileraxles 120, by way of the electric motor-generator 130. In variousexamples, the driven one or more trailer axles 120 may provide feedbackto the control system 150, for further computation and application oftorque. In some cases, the one or more driven trailer axles 120 may alsoprovide feedback to the electric motor-generator 130. In at least someembodiments, the hybrid suspension system 100 may sense one or morepneumatic brake lines from the powered vehicle.

Referring to FIG. 6B, illustrated therein is an exemplary functionalblock diagram 630 for controlling the adapted hybrid system 101,described above. In particular, the block diagram 630 illustratesexemplary relationship, in at least some embodiments, among variouscomponents of a tractor, such as the tractor 165 of FIG. 10 or 1E. Someaspects of the methods 500, 550, discussed above, may be furtherelaborated upon and understood with reference to FIG. 6B. For example,FIG. 6B illustrates the autonomous nature of the adapted hybrid system101, where the adapted hybrid system 101 is able to operate withoutdirect commands or signals from the driver or other components of thepowered vehicle, to independently gain information about itself, thetractor 165, and the environment (e.g., by way of the sensing system),and to make decisions and/or perform various functions based on one ormore algorithms stored in the control system 150. To be sure, in someembodiments, the adapted hybrid system 101 may retrieve and/or sharedata, for example, via the CAN bus of the tractor 165.

The autonomous nature of the adapted hybrid system 101 is furtherexemplified, in at least some embodiments, by the functional blockdiagram 630 including two separate control loops, an adapted hybridsystem control loop 640 and the powered vehicle control loop 620, whichis substantially as described above. Independent from the poweredvehicle control loop 620, the adapted hybrid system control loop 640 mayoperate in a substantially similar manner to the methods 500, 550described above. For example, in at least some embodiments, the controlsystem 150 may receive tractor data from a sensor system 602 (e.g.,which may be part of the adapted hybrid system 101 and/or coupled to thetractor 165), which may include any of the one or more sensors discussedabove. In some cases, the sensor system 602 may include the on-boardsensors discussed above. In some embodiments, the control system 150 maycompute a total estimated torque and computationally estimate a torqueapplied by the engine of the tractor 165. In some embodiments, based onthe total estimated torque and the computationally estimated torque ofthe powered vehicle, a specified torque may be computed and applied toone or more electric axles of the tractor 165, by way of one or moreelectric motor-generators 130, as shown in FIGS. 10 and 1E. In variousexamples, the electric axle of the tractor 165 may provide feedback tothe control system 150, for further computation and application oftorque. In some cases, the one or more electric axles of the tractor 165may also provide feedback to the one or more electric motor-generators130. In at least some embodiments, the adapted hybrid system 101 maysense one or more pneumatic brake lines.

With reference to FIG. 6C, illustrated therein is an exemplaryfunctional block diagram 650 for controlling both the hybrid suspensionsystem 100 and the adapted hybrid system 101, described above. Inparticular, the block diagram 650 illustrates exemplary relationship, inat least some embodiments, among various components an HVTS, where thehybrid suspension system 100 and the adapted hybrid system 101 may becooperatively operated. Some aspects of the methods 500, 550, discussedabove, may be further elaborated upon and understood with reference toFIG. 6C.

In particular, the cooperative operation of the hybrid suspension system100 and the adapted hybrid system 101, together with the powered vehicleengine, is illustrated by the functional block diagram 650. As shown inFIG. 6C, the functional block diagram 650 includes three separatecontrol loops, the hybrid suspension system control loop 610, theadapted hybrid system control loop 640, and the powered vehicle controlloop 620. Independent from the powered vehicle control loop 650, each ofthe hybrid suspension control loop 610 and the adapted hybrid systemcontrol loop 640 may operate in a substantially similar manner asdescribed above. In some embodiments, the hybrid suspension systemcontrol loop 610 and the adapted hybrid system control loop 640 mayshare a control system 150 (e.g., housed within one of the hybridsuspension system 100 or the adapted hybrid system 101), or each of thecontrol loops 610, 640 may utilize separate control systems 150 (e.g.,housed within each of the hybrid suspension system 100 and the adaptedhybrid system 101). Moreover, in some embodiments, the control system150 may receive sensor data from the sensor system 602, where thesensors may be housed and/or coupled to one or more of the trailer, thetractor, the hybrid suspension system 100, and the adapted hybrid system101.

In various embodiments, the control system 150 may compute a totalestimated torque and computationally estimate a torque applied by theengine of the tractor 165. In some embodiments, based on the totalestimated torque and the computationally estimated torque of the poweredvehicle (e.g., the engine of the tractor 165), a specified torque may becomputed and applied to one or more electric axles of the tractor 165,as well as to the one or more trailer axles 120, by way of one or moreelectric motor-generators 130. In various examples, the electric axle ofthe tractor 165 and the one or more trailer axles 120 may providefeedback to the control system 150, for further computation andapplication of torque. In some cases, the one or more electric axles ofthe tractor 165 and the one or more trailer axles 120 may also providefeedback to the one or more electric motor-generators 130.

Control Methods, Examples and Further Discussion

The hybrid suspension system 100 and/or the adapted hybrid system 101may be used, for example together with aspects of the control methodsdescribed above, to operate in a variety of different modes (e.g., powerassist, regeneration, and passive modes) and thus perform a variety ofdifferent functions. In various examples, the hybrid suspension system100 and/or the adapted hybrid system 101 may be used to provide a powerboost (e.g., to the HVTS) during acceleration and/or when going up anincline by operating in the power assist mode, thereby depleting energyfrom the energy storage system. In addition, the hybrid suspensionsystem 100 and/or the adapted hybrid system 101 may replenish thatenergy by operating in the regeneration mode (e.g., using regenerativebraking) when decelerating and/or when going down a decline. Asdiscussed above, operation in one of the various modes may be determinedaccording to a variety of inputs and/or data (e.g., from sensors,calculated values, etc.) such as discussed above. In various examples,the hybrid suspension system 100 and/or the adapted hybrid system 101and associated methods may provide, among other benefits, optimalapplication of power (e.g., as discussed in the example below),increased fuel mileage, decreased fuel emissions, and superior loadstabilization. Of particular note, embodiments of the hybrid suspensionsystem 100 described herein are configured to operate independently ofthe powered vehicle to which the trailer may be attached. Thus, any typeof powered vehicle may hook up and tow a trailer, including the hybridsuspension system 100 attached thereunder, and the hybrid suspensionsystem 100 will automatically adapt to the powered vehicle's behavior.Similarly, embodiments of the adapted hybrid system 101 are configuredto replace a passive axle of any type of tractor with an electric axle,as described above, and independent operate and adapt to the behavior(e.g., throttle/braking) of the tractor.

With respect to optimal application of power as discussed above, thereare scenarios in which battery power could be used most effectively at agiven time, for example, knowing that battery power may be (i)regenerated in the near future (e.g., based on an upcoming downhillroadway grade) or (ii) needed in the near future (e.g., based on anupcoming uphill roadway grade). Such information (e.g., regarding theupcoming roadway) may be gathered from GPS data, inclinometer data,and/or other sensor data as described above. In some embodiments, thehybrid suspension system 100 and/or the adapted hybrid system 101 mayalternatively and/or additionally periodically query a network server,or other remote sever/database, to provide an upcoming roadway grade.

For purposes of illustration, consider an example where an HTVS istraveling along substantially flat terrain, while the battery array 140of the hybrid suspension system 100 is at about a 70% state of charge(SOC). Consider also that there is an extended downhill portion ofroadway coming up that would provide for regeneration about 40% SOC ofthe battery array 140 (e.g., while operating the hybrid suspensionsystem 100 in the regeneration mode). Absent knowledge of the upcomingextended downhill portion of the roadway, some embodiments may operatein the passive mode on the substantially flat terrain, while beginningto regenerate the battery array 140 once the HTVS reaches the extendeddownhill portion of roadway. In such cases, about 30% SOC may beregenerated before the battery array 140 is fully charged. Thus, thesystem may not be able to regenerate further, and about 10% SOC thatcould have been captured may be lost.

In some embodiments, the predictive road ability discussed hereinprovides knowledge of the upcoming extended downhill portion of roadway.As such, the hybrid suspension system 100 may autonomously engage thepower assist mode while traveling along the substantially flat terrain,such that about 10% SOC of the battery array 140 is used prior toreaching the extended downhill portion of roadway, thereby improvingfuel efficiency of the HTVS (e.g., while on the substantially flatterrain), while still regenerating about 30% SOC while traveling alongthe extended downhill portion. Such system operation, including thepredictive road ability, advantageously provides for both improved fuelefficiency of the HTVS efficient use of the battery array 140 (e.g., asit may be undesirable to have the battery array nearly full or nearlyempty when there is an opportunity to regenerate or provide powerassistance).

In another example, consider a case where the battery array 140 is atabout 10% SOC and the HTVS is traveling along substantially flatterrain. Consider also that an extended uphill portion of roadway iscoming up that would optimally be able to use about 20% SOC of thebattery array 140 (e.g., while operating the hybrid suspension system100 in the power assist mode). Once again, absent knowledge of theupcoming extended uphill portion of the roadway, some embodiments mayoperate in the passive mode on the substantially flat terrain, whilebeginning to use energy (e.g., operating in the power assist mode) oncethe HTVS reaches the extended uphill portion of the roadway. Thus, insuch an example, the battery array 140 may expend its 10% SOC before thehybrid suspension system 100 may not be able to assist further. Statedanother way, about 10% SOC that could have been effectively used by theHTVS while traveling along the extended uphill portion of the roadway isnot available.

As discussed above, the predictive road ability provides knowledge ofthe upcoming extended downhill portion of roadway. As such, the hybridsuspension system 100 may autonomously engage the regeneration modewhile traveling along the substantially flat terrain, such that about10% SOC of battery array 140 is regenerated, for a total of about 20%SOC, prior to reaching the extended uphill portion of the roadway. Whilethis may result in a temporary decrease in fuel efficiency, theefficiency gains afforded by operating the hybrid suspension system 100in the power assist mode for the duration of the extended uphill portionof the roadway (e.g., and optimally using the 20% SOC of the batteryarray 140) outweigh any potential efficiency reductions that may occurby regenerating on the substantially flat terrain. While the examplesabove were described primarily with reference to the hybrid suspensionsystem 100, it will be understood that similar predictive road ability,and associated benefits, may be similarly employed using the adaptedhybrid system 101.

In addition to using the various sensors, data, networking capabilities,etc. to determine whether the HTVS is traveling along substantially flatterrain, uphill, or downhill, embodiments of the present disclosure maybe used to determine whether the HTVS is hitting a bump or pothole,turning a corner, and/or accelerating. By accounting for dynamics of thetrailer and measuring angles and accelerations (e.g., in 3-dimensionalspace), embodiments of the present disclosure may provide formeasurement of: (i) acceleration, deceleration, and angle of inclinationof the trailer (e.g., by taking readings lengthwise), (ii) side-to-side(e.g., turning force) motion and banking of a roadway (e.g., by takingreadings widthwise), (iii) smoothness of the roadway, pot holes, and/orwheels riding on a shoulder (side) of the road (e.g., by taking readingsvertically). Utilizing such information, embodiments of the presentdisclosure may be used to brake wheels individually, for example, whilestill supplying power (e.g., by the power assist mode) to other wheels,thereby increasing trailer stability. In addition, and in someembodiments, by monitoring the acceleration, axle speed and incline ofthe roadway over time and by applying an incremental amount of torqueand measuring the response in real time, the controller mayback-calculate a mass of the trailer load. In some embodiments, a weightsensor may also be used, as described above. In either case, suchinformation may be used by the system for application of a proper amountof torque to assist in acceleration of the HTVS without over-pushing thepowered vehicle.

In some examples, the system may further be used to monitor one or morepneumatic brake lines, such that embodiments of the present disclosureprovide a ‘fail safe’ mode where the hybrid suspension system 100 and/orthe adapted hybrid system 101 will not accelerate (e.g., operate in apower assist mode) while a driver (e.g. of the powered vehicle) isactuating a brake system. In various embodiments, by monitoring feedbackpressure of each wheel's brake lines, as well as their respective wheelspeeds, the present system can determine how each brake for a particularwheel is performing. Thus, in various examples, embodiments of thepresent disclosure may provide for braking and/or powering of differentwheels independently from one another for increased trailer stability.In some cases, this may be referred to as “torque vectoring”. By way ofexample, such torque vectoring embodiments may be particularly usefulwhen there are differences in roadway surfaces upon which each of aplurality of wheels of the HTVS is traveling (e.g., when roadwayconditions are inconsistent, slippery, rough, etc.).

In various embodiments, embodiments disclosed herein may further beemployed to recapture energy via regenerative braking, as describedabove. In some examples, the application of the brakes, and/or variouscombinations of deceleration, axle speed, trailer weight andincline/decline readings may dictate, at least in part, an ability andamount of regeneration possible by the hybrid suspension system 100and/or the adapted hybrid system 101. In various embodiments,regenerative braking may persist until the energy storage system isfully charged, until a predetermined minimum level of stored energy hasbeen achieved, or until the powered trailer axle has reached a minimumthreshold rotational speed. Additionally, for example in some extremeconditions, different amounts of braking may be be applied to each wheelin order to reduce a potential of jack-knifing or other dangerousconditions during operation of the HTVS. As a whole, regenerativebraking may be used to lighten a load on a mechanical braking system(e.g., on the powered vehicle and/or on the trailer), thereby virtuallyeliminating a need for a loud compression release engine brake system(e.g., Jake brake system). In some cases, by applying both regenerativebraking and friction braking, the HTVS may be able to brake much fasterand have shorter stopping distances. In addition, and in variousembodiments, the present system may be deployed with two pneumatic brakelines (e.g., which may including existing brake lines), while anentirety of the controls (e.g., including sensor input processing, modeof operation control, aspects of the various methods described above,and other decision-making controls) may reside entirely within thehybrid suspension system 100 and/or the adapted hybrid system 101 itself(e.g., and in many respects, within the control system 150).

Computer System for Implementing the Various Methods

Referring now to FIG. 7, an embodiment of a computer system 700 suitablefor implementing various aspects of the control system 150 and methods500, 550, is illustrated. It should be appreciated that any of a varietyof systems which are used for carrying out the methods described herein,as discussed above, may be implemented as the computer system 700 in amanner as follows.

In accordance with various embodiments of the present disclosure,computer system 700, such as a computer and/or a network server,includes a bus 702 or other communication mechanism for communicatinginformation, which interconnects subsystems and components, such as aprocessing component 704 (e.g., processor, micro-controller, digitalsignal processor (DSP), etc.), a system memory component 706 (e.g.,RAM), a static storage component 708 (e.g., ROM), a disk drive component710 (e.g., magnetic or optical), a network interface component 712(e.g., modem or Ethernet card), a display component 714 (e.g., CRT orLCD), an input component 718 (e.g., keyboard, keypad, or virtualkeyboard), a cursor control component 720 (e.g., mouse, pointer, ortrackball), a location determination component 722 (e.g., a GlobalPositioning System (GPS) device as illustrated, a cell towertriangulation device, and/or a variety of other location determinationdevices known in the art), and/or a camera component 723. In oneimplementation, the disk drive component 710 may comprise a databasehaving one or more disk drive components.

In accordance with embodiments of the present disclosure, the computersystem 700 performs specific operations by the processor 704 executingone or more sequences of instructions contained in the memory component706, such as described herein with respect to the control system 150 andmethods 500, 550. Such instructions may be read into the system memorycomponent 706 from another computer readable medium, such as the staticstorage component 708 or the disk drive component 710. In otherembodiments, hard-wired circuitry may be used in place of or incombination with software instructions to implement the presentdisclosure.

Logic may be encoded in a computer readable medium, which may refer toany medium that participates in providing instructions to the processor704 for execution. Such a medium may take many forms, including but notlimited to, non-volatile media, volatile media, and transmission media.In one embodiment, the computer readable medium is non-transitory. Invarious implementations, non-volatile media includes optical or magneticdisks, such as the disk drive component 710, volatile media includesdynamic memory, such as the system memory component 706, andtransmission media includes coaxial cables, copper wire, and fiberoptics, including wires that comprise the bus 702. In one example,transmission media may take the form of acoustic or light waves, such asthose generated during radio wave and infrared data communications.

Some common forms of computer readable media includes, for example,floppy disk, flexible disk, hard disk, magnetic tape, any other magneticmedium, CD-ROM, any other optical medium, punch cards, paper tape, anyother physical medium with patterns of holes, RAM, PROM, EPROM,FLASH-EPROM, any other memory chip or cartridge, carrier wave, or anyother medium from which a computer is adapted to read. In oneembodiment, the computer readable media is non-transitory.

In various embodiments of the present disclosure, execution ofinstruction sequences to practice the present disclosure may beperformed by the computer system 700. In various other embodiments ofthe present disclosure, a plurality of the computer systems 700 coupledby a communication link 724 to a network (e.g., such as a LAN, WLAN,PTSN, and/or various other wired or wireless networks, includingtelecommunications, mobile, and cellular phone networks) may performinstruction sequences to practice the present disclosure in coordinationwith one another.

The computer system 700 may transmit and receive messages, data,information and instructions, including one or more programs (i.e.,application code) through the communication link 724 and the networkinterface component 712. The network interface component 712 may includean antenna, either separate or integrated, to enable transmission andreception via the communication link 724. Received program code may beexecuted by processor 704 as received and/or stored in disk drivecomponent 710 or some other non-volatile storage component forexecution.

Where applicable, various embodiments provided by the present disclosuremay be implemented using hardware, software, or combinations of hardwareand software. Also, where applicable, the various hardware componentsand/or software components set forth herein may be combined intocomposite components comprising software, hardware, and/or both withoutdeparting from the scope of the present disclosure. Where applicable,the various hardware components and/or software components set forthherein may be separated into sub-components comprising software,hardware, or both without departing from the scope of the presentdisclosure. In addition, where applicable, it is contemplated thatsoftware components may be implemented as hardware components andvice-versa.

Software, in accordance with the present disclosure, such as programcode and/or data, may be stored on one or more computer readablemediums. It is also contemplated that software identified herein may beimplemented using one or more general purpose or specific purposecomputers and/or computer systems, networked and/or otherwise. Whereapplicable, the ordering of various steps described herein may bechanged, combined into composite steps, and/or separated into sub-stepsto provide features described herein.

What is claimed is:
 1. A method, comprising: supplying supplementaltorque to one or more wheels of a vehicle for use in a tractor-trailervehicle configuration using an electrically powered drive axle on thevehicle to supplement, while the vehicle travels over a roadway, primarymotive forces applied through a separate drivetrain of the vehicle; andsupplying the electrically powered drive axle with electrical power froman energy store on the vehicle, the energy store configured to receiveand store energy recovered using the electrically powered drive axle ina regenerative braking mode of operation.
 2. The method of claim 1,wherein the vehicle is a tractor unit.
 3. The method of claim 2, whereinthe tractor unit is retrofitted to replace a dead axle of a tandem pairwith the electrically powered drive axle.
 4. The method of claim 2,wherein the tractor unit is a 6×2 tractor unit.
 5. The method of claim1, wherein the energy store includes a battery.
 6. The method of claim1, comprising controllably maintaining a desired state of charge (SoC)of the energy store.
 7. The method of claim 6, wherein the SoC ismaintained by a battery management system during the over-the-roadwaytravel.
 8. The method of claim 1, comprising moderating temperature ofthe energy store.
 9. The method of claim 8, wherein the temperature ismoderated by a heat exchanger during the over-the-roadway travel. 10.The method of claim 1, comprising supplying electrical power from theenergy store to a heating, ventilation or cooling (HVC) system on thevehicle.
 11. A non-transitory computer readable medium comprisinginstructions that when read by a processor, cause the processor toperform: supplying supplemental torque to one or more wheels of avehicle for use in a tractor-trailer vehicle configuration using anelectrically powered drive axle on the vehicle to supplement, while thevehicle travels over a roadway, primary motive forces applied through aseparate drivetrain of the vehicle; and supplying the electricallypowered drive axle with electrical power from an energy store on thevehicle, the energy store configured to receive and store energyrecovered using the electrically powered drive axle in a regenerativebraking mode of operation.
 12. The non-transitory computer readablemedium of claim 11, wherein the vehicle is a tractor unit.
 13. Thenon-transitory computer readable medium of claim 12, wherein the tractorunit is retrofitted to replace a dead axle of a tandem pair with theelectrically powered drive axle.
 14. The non-transitory computerreadable medium of claim 12, wherein the tractor unit is a 6×2 tractorunit.
 15. The non-transitory computer readable medium of claim 11,wherein the energy store includes a battery.
 16. The non-transitorycomputer readable medium of claim 11, wherein the instructions arefurther configured to perform controllably maintaining a desired stateof charge (SoC) of the energy store.
 17. The non-transitory computerreadable medium of claim 16, wherein the SoC is maintained by a batterymanagement system during the over-the-roadway travel.
 18. Thenon-transitory computer readable medium of claim 11, wherein theinstructions are further configured to perform moderating temperature ofthe energy store.
 19. The non-transitory computer readable medium ofclaim 18, wherein the temperature is moderated by a heat exchangerduring the over-the-roadway travel.
 20. The non-transitory computerreadable medium of claim 11, wherein the instructions are furtherconfigured to perform supplying electrical power from the energy storeto a heating, ventilation or cooling (HVC) system on the vehicle.